Question

The human population of Earth was approximately 6 billion in 1998. If the rate of

population growth from then on was 2.3% per year, what would be the best
approximation for the human population (in billions) of Earth in 2020?

Answer 1

Let the equation for the population (P) growth be given by

P = P0ert, where P0 is the initial population in billioins at time t,

t is the number of years since 1987,

r is the rate of growth of population/year

In this case P0 = 5 billion and r = 0.02. Putting these values into the equaation:

P = 5e0.02t

Year 1995 is 8 years after 1987, then the population would be

P = 5e0.02*8 = 5e0.16 ≈ 5.87 billion people

Explanation:

Answer 2

9.89 billion

Explanation:

At that rate of growth, the population is multiplied by 1.023 each year. After 22 years, the population would be ...

6·1.023^22 ≈ 9.89 . . . billion